1. Field of the Invention
The present invention relates to a pump for inflating a bicycle tire or ball, and more particularly to a pump capable of preventing reverse airflow or air leakage.
2. The Prior Arts
U.S. Pat. No. 6,350,112 discloses a dual-direction pump comprising a head portion composed of two cylinders arranged on opposite sides of the head portion, and a connector mounted to the head portion for releasable connection with a valve of tire for inflation.
Since conventionally, the inflation connector is coupled to the head portion in a non-secured manner, it is liable to come off because of vibration or due to reasons whatsoever during inflating. Moreover, as there is no return-flow prevention device available in the head portion, both cylinders have to work simultaneously in order to prevent air from leaking through the other side.